Numerical wind tunnel analysis method for middle-span inclination-angle-adjustable flexible photovoltaic support

Abstract

The embodiment of the invention provides a numerical wind tunnel analysis method for a middle-span inclination-angle-adjustable flexible photovoltaic support, and relates to the technical field of photovoltaic power generation. According to the method, a first wind field model is established to perform a numerical wind tunnel test on a three-dimensional model of a monomer structure so as to perform strength checking on the middle-span inclination-angle-adjustable flexible photovoltaic support; and a numerical wind tunnel test is carried out on the multi-body uniformly distributed array three-dimensional model by establishing a second wind field model so as to carry out resonance monitoring on the middle-span inclination-angle-adjustable flexible photovoltaic support, the numerical wind tunnel test is carried out by taking a single target as a test object, and meanwhile, the influence of interaction among multiple targets on a test result is also considered. Therefore, the accuracy of a numerical wind tunnel test result is improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of photovoltaic power generation technology, and in particular to a numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic bracket. Background Art

[0002] At present, with the gradual promotion of flexible photovoltaic brackets, the adaptability of photovoltaic bracket installation scenarios has been greatly improved. However, the support strength and rigidity of flexible brackets for photovoltaic modules have been greatly reduced. The traditional static wind load force calculation method cannot judge wind-induced vibration and other situations. It is necessary to introduce a dynamic wind load force analysis method. However, there is currently no reference standard.

[0003] At the same time, because traditional brackets cannot automatically flatten under extreme wind speed conditions, flexible brackets with adjustable inclination angles have appeared on the market. Since the windward angle of the component changes with the solar altitude, it becomes more difficult to determine the value of the shape coefficient for the wind load force calculation formula. The traditional load analysis empirical data value standard is no longer applicable.

[0004] In addition, wind tunnel testing is a traditional method for dynamic wind load analysis. However, since the size of the sample to be tested is too large relative to the size of the wind tunnel, it must be scaled down. Scaled samples will lead to large deviations in fluid mechanics properties, such as the natural frequency of the flexible bracket and the torque value of the fastener, which cannot be accurately determined. Therefore, the results of the wind tunnel test can only be used for reference.

[0005] In summary, in view of the lack of dynamic wind load analysis standards for flexible brackets, the traditional value standards such as shape coefficient are no longer applicable due to the adjustable inclination angle, and the inaccurate results of scaled wind tunnel tests, a numerical wind tunnel analysis method for mid-span adjustable inclination flexible photovoltaic bracket is urgently needed. Summary of the invention

[0006] In view of the above problems, an embodiment of the present application provides a numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic bracket, so as to overcome the above problems or at least partially solve the above problems.

[0007] In a first aspect of an embodiment of the present application, a wind tunnel test method for a mid-span adjustable tilt flexible photovoltaic bracket is provided, the method comprising:

[0008] S1. Obtain design parameters of mid-span adjustable tilt flexible photovoltaic support;

[0009] S2. According to the design parameters, a three-dimensional model of the monomer structure of the mid-span adjustable tilt flexible photovoltaic support is established with the tilt angle of the photovoltaic module as the first initial angle;

[0010] S3. Establishing a first wind field model according to the three-dimensional model of the monomer structure, wherein the angle between the inlet of the first wind field model and the windward surface of the three-dimensional model of the monomer structure is a second initial angle;

[0011] S4. Based on the first wind field model, performing strength verification on the mid-span adjustable tilt flexible photovoltaic support;

[0012] S5, evenly arranging the plurality of said monomer structure three-dimensional models to establish a multi-body evenly distributed array three-dimensional model;

[0013] S6. Establishing a second wind field model according to the multi-body uniformly distributed array three-dimensional model, wherein the angle between the inlet of the second wind field model and the windward surface of the uniformly distributed array three-dimensional model is the second initial angle;

[0014] S7. Based on the second wind field model, performing resonance monitoring on the mid-span adjustable tilt flexible photovoltaic support;

[0015] S8, adjusting the first initial angle according to a first preset interval angle, and repeating steps S1-S7;

[0016] S9. Adjust the second initial angle according to a second preset interval angle, and repeat steps S1-S8.

[0017] Optionally, step S4 includes:

[0018] S4.1. In the first wind field model, select a first preset turbulence model;

[0019] S4.2. Setting a first boundary condition of the first wind field model, the first boundary condition comprising: a first initial pressure and a first initial velocity;

[0020] S4.3. Based on the first preset turbulence model and the first boundary condition, a numerical wind tunnel calculation is performed by finite element analysis software to determine wind pressure parameters distributed on the photovoltaic panels of the three-dimensional model of the single structure;

[0021] S4.4 determining the shape coefficient of the three-dimensional model of the single structure and the gust coefficient of the wind load in the first wind field model according to the wind pressure parameter;

[0022] S4.5. Based on the shape coefficient and the gust coefficient, the strength of the photovoltaic bracket of the single-body structure three-dimensional model is checked by using the wind load statics equation.

[0023] Optionally, the strength check of the photovoltaic support of the three-dimensional model of the single structure is performed by using the static mechanics equation of wind load, including:

[0024] Obtaining the structural strength of the photovoltaic support of the single structure three-dimensional model;

[0025] By using the wind load statics equation, the intensity of the wind load acting on the photovoltaic support in the first wind field model is calculated;

[0026] Based on the structural strength of the photovoltaic bracket and the strength of the wind load acting on the photovoltaic bracket, the photovoltaic bracket of the single-body three-dimensional model is strength-checked.

[0027] Optionally, the step S4 further includes:

[0028] S4.6. When the structural strength of the photovoltaic bracket in the three-dimensional model of the single structure is lower than the strength of the wind load acting on the photovoltaic bracket, the structural strength of the photovoltaic bracket in the three-dimensional model of the single structure is strengthened.

[0029] Optionally, the step S7 includes:

[0030] S7.1. In the second wind field model, select a second preset turbulence model;

[0031] S7.2. Setting a second boundary condition of the second wind field model, the second boundary condition comprising: a second initial pressure and a second initial velocity;

[0032] S7.3. Based on the second preset turbulence model and the second boundary condition, a numerical wind tunnel calculation is performed by finite element analysis software to determine the transition flow characteristics between any two adjacent three-dimensional models of the single structure in the multi-body uniformly distributed array three-dimensional model;

[0033] S7.4. Determine whether resonance occurs between any two adjacent three-dimensional models of the monomer structure according to the transition flow characteristics.

[0034] Optionally, determining whether resonance occurs between any two adjacent three-dimensional models of the monomer structure according to the transition flow characteristics includes:

[0035] determining a swing frequency of the transition flow according to the transition flow characteristics;

[0036] Performing modal analysis on any two adjacent three-dimensional models of the monomer structure in the multi-body uniformly distributed array three-dimensional model using finite element analysis software to determine the vibration frequency corresponding to the free vibration mode of any two adjacent three-dimensional models of the monomer structure;

[0037] When the oscillation frequency of the transitional flow is the same as the vibration frequency corresponding to the free vibration mode, it is determined that resonance occurs between any two adjacent three-dimensional models of the monomer structure.

[0038] Optionally, the step S7 further includes:

[0039] S7.5. When it is determined that resonance will occur between any two adjacent three-dimensional models of the monomer structure, the structural parameters of the photovoltaic brackets of the two adjacent three-dimensional models of the monomer structure are corrected.

[0040] Optionally, the step S3 of establishing a first wind field model according to the monomer structure three-dimensional model includes:

[0041] Taking the monomer structure three-dimensional model as a reference, the entrance of the first wind field model is established at a first preset distance from the windward side of the monomer structure three-dimensional model, the exit of the first wind field model is established at a second preset distance from the leeward side of the monomer structure three-dimensional model, and the boundaries of the first wind field model are established at third preset distances from both sides and the top of the monomer structure three-dimensional model.

[0042] Optionally, the step S6 of establishing a second wind field model according to the multi-body uniformly distributed array three-dimensional model includes:

[0043] Taking the multi-body evenly distributed array three-dimensional model as a reference, the entrance of the second wind field model is established at a first preset distance from the windward side of the multi-body evenly distributed array three-dimensional model, the exit of the second wind field model is established at a second preset distance from the leeward side of the multi-body evenly distributed array three-dimensional model, and the boundaries of the second wind field model are established at third preset distances from both sides and above the multi-body evenly distributed array three-dimensional model.

[0044] Optionally, the first initial angle is 5 degrees, the first preset interval angle is 5 degrees, and adjusting the first initial angle according to the first preset interval angle includes:

[0045] Taking the first initial angle of 5 degrees as a reference, according to the first preset interval angle of 5 degrees, the first initial angle is adjusted to 10 degrees, 15 degrees, 20 degrees, 25 degrees, and 30 degrees respectively.

[0046] Optionally, the second initial angle is 0 degrees, the second preset interval angle is 15 degrees, and adjusting the second initial angle according to the second preset interval angle includes:

[0047] Taking the second initial angle of 0 degrees as a reference, according to the second preset interval angle of 15 degrees, the second initial angle is adjusted to 15 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees, 90 degrees, 105 degrees, 120 degrees, 135 degrees, 150 degrees, 165 degrees, and 180 degrees respectively.

[0048] This application has the following advantages:

[0049] The embodiment of the present application provides a method for numerical wind tunnel analysis of a mid-span flexible photovoltaic bracket with adjustable inclination, the method comprising: S1, obtaining design parameters of the mid-span flexible photovoltaic bracket with adjustable inclination; S2, establishing a three-dimensional model of the monomer structure of the mid-span flexible photovoltaic bracket with adjustable inclination based on the design parameters and taking the inclination angle of the photovoltaic module as the first initial angle; S3, establishing a first wind field model based on the three-dimensional model of the monomer structure, wherein the angle between the inlet of the first wind field model and the windward surface of the three-dimensional model of the monomer structure is the second initial angle; S4, performing a strong wind tunnel analysis on the mid-span flexible photovoltaic bracket with adjustable inclination based on the first wind field model. degree verification; S5, evenly arrange multiple three-dimensional models of the single structure to establish a multi-body evenly distributed array three-dimensional model; S6, establish a second wind field model based on the multi-body evenly distributed array three-dimensional model, and the angle between the inlet of the second wind field model and the windward surface of the evenly distributed array three-dimensional model is the second initial angle; S7, based on the second wind field model, perform resonance monitoring on the mid-span adjustable tilt flexible photovoltaic bracket; S8, adjust the first initial angle according to the first preset interval angle, and repeat steps S1-S7; S9, adjust the second initial angle according to the second preset interval angle, and repeat steps S1-S8. The present application establishes a first wind field model to conduct numerical wind tunnel tests on a single-body structure three-dimensional model to perform strength verification on a mid-span flexible photovoltaic bracket with adjustable tilt, and establishes a second wind field model to conduct numerical wind tunnel tests on a multi-body uniformly distributed array three-dimensional model to perform resonance monitoring on the mid-span flexible photovoltaic bracket with adjustable tilt. Not only does the numerical wind tunnel test take a single target as the test object, but also takes into account the impact of the interaction between multiple targets on the test results, thereby improving the accuracy of the numerical wind tunnel test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0051] Figure 1 It is a schematic diagram of the steps of a numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic bracket provided in an embodiment of the present application;

[0052] Figure 2 It is a schematic diagram of a three-dimensional model of a monomer structure of a mid-span adjustable tilt flexible photovoltaic bracket provided in an embodiment of the present application;

[0053] Figure 3 It is a schematic diagram of a three-dimensional model of a multi-body uniformly distributed array of a mid-span adjustable tilt flexible photovoltaic bracket provided in an embodiment of the present application;

[0054] Figure 4 It is a schematic diagram of a curve showing the relationship between frequency and amplitude of a mid-span adjustable tilt flexible photovoltaic bracket provided in an embodiment of the present application;

[0055] Figure 5 It is a structural schematic diagram of a first wind field model and an edge space of a monomer structure three-dimensional model provided in an embodiment of the present application;

[0056] Figure 6 This is a schematic diagram of the component inclination angle of a mid-span adjustable inclination flexible photovoltaic bracket provided in an embodiment of the present application;

[0057] Figure 7 It is a schematic diagram of a multi-body uniformly distributed array three-dimensional model provided in an embodiment of the present application and a second wind field model when the relative position angle is 0 degrees;

[0058] Figure 8 It is a schematic diagram of a multi-body uniformly distributed array three-dimensional model provided in an embodiment of the present application and a second wind field model when the relative position angle is 15 degrees;

[0059] Fig. 9 It is a schematic diagram of a multi-body uniformly distributed array three-dimensional model provided in an embodiment of the present application and a second wind field model when the relative position angle is 30 degrees;

[0060] Fig.10 It is a schematic diagram of a multi-body uniformly distributed array three-dimensional model provided in an embodiment of the present application and a second wind field model when the relative position angle is 45 degrees;

[0061] Fig.11 It is a schematic diagram of a multi-body uniformly distributed array three-dimensional model provided in an embodiment of the present application and a second wind field model when the relative position angle is 60 degrees;

[0062] Fig.12 It is a schematic diagram of a multi-body uniformly distributed array three-dimensional model and a wind field model provided in an embodiment of the present application when the relative position angle is 75 degrees;

[0063] Fig.13 It is a schematic diagram of a multi-body uniformly distributed array three-dimensional model provided in an embodiment of the present application and a second wind field model when the relative position angle is 90 degrees;

[0064] Fig.14 It is a schematic diagram of a multi-body uniformly distributed array three-dimensional model provided in an embodiment of the present application and a second wind field model when the relative position angle is 105 degrees;

[0065] Fig.15 It is a schematic diagram of a multi-body uniformly distributed array three-dimensional model provided in an embodiment of the present application and a second wind field model when the relative position angle is 120 degrees;

[0066] Fig.16 It is a schematic diagram of a multi-body uniformly distributed array three-dimensional model provided in an embodiment of the present application and a second wind field model when the relative position angle is 135 degrees;

[0067] Fig.17 It is a schematic diagram of a multi-body uniformly distributed array three-dimensional model provided in an embodiment of the present application and a second wind field model when the relative position angle is 150 degrees;

[0068] Fig.18 It is a schematic diagram of a multi-body uniformly distributed array three-dimensional model provided in an embodiment of the present application and a second wind field model when the relative position angle is 165 degrees;

[0069] Fig.19 It is a schematic diagram of a multi-body uniformly distributed array three-dimensional model provided in an embodiment of the present application and a second wind field model when the relative position angle is 180 degrees. DETAILED DESCRIPTION

[0070] The exemplary embodiments of the present application will be described in more detail below in conjunction with the accompanying drawings in the embodiments of the present application. Although the exemplary embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present application and to enable the scope of the present application to be fully communicated to those skilled in the art.

[0071] In a first aspect of the present application, a method for numerical wind tunnel analysis of a mid-span adjustable tilt flexible photovoltaic bracket is provided. Figure 1 As shown, the method includes:

[0072] S1. Obtain design parameters of mid-span adjustable tilt flexible photovoltaic support;

[0073] S2. According to the design parameters, a three-dimensional model of the monomer structure of the mid-span adjustable tilt flexible photovoltaic support is established with the tilt angle of the photovoltaic module as the first initial angle;

[0074] S3. Establishing a first wind field model according to the three-dimensional model of the monomer structure, wherein the angle between the inlet of the first wind field model and the windward surface of the three-dimensional model of the monomer structure is a second initial angle;

[0075] S4. Based on the first wind field model, performing strength verification on the mid-span adjustable tilt flexible photovoltaic support;

[0076] S5, evenly arranging the plurality of said monomer structure three-dimensional models to establish a multi-body evenly distributed array three-dimensional model;

[0077] S6. Establishing a second wind field model according to the multi-body uniformly distributed array three-dimensional model, wherein the angle between the inlet of the second wind field model and the windward surface of the uniformly distributed array three-dimensional model is the second initial angle;

[0078] S7. Based on the second wind field model, performing resonance monitoring on the mid-span adjustable tilt flexible photovoltaic support;

[0079] S8, adjusting the first initial angle according to a first preset interval angle, and repeating steps S1-S7;

[0080] S9. Adjust the second initial angle according to a second preset interval angle, and repeat steps S1-S8.

[0081] Specifically, in this embodiment, it is first necessary to obtain the key parameters of the mid-span adjustable tilt flexible photovoltaic bracket in the current project. The key parameters of the mid-span adjustable tilt flexible photovoltaic bracket can be the size, material, etc. of the bracket. Based on the key parameters of the mid-span adjustable tilt flexible photovoltaic bracket obtained, the following is made: Figure 2 The three-dimensional monomer structure model of the mid-span adjustable tilt flexible photovoltaic bracket is shown, wherein, for the three-dimensional monomer structure model of the mid-span adjustable tilt flexible photovoltaic bracket, the tilt angle of the photovoltaic module therein is preset as a first initial angle. Then, based on the three-dimensional monomer structure model, a first wind field model corresponding to the three-dimensional monomer structure model is established, and the angle between the first wind field model and the windward surface of the three-dimensional monomer structure model is preset as a second initial angle. Finally, the strength of the mid-span adjustable tilt flexible photovoltaic bracket is checked through the first wind field model.

[0082] Furthermore, multiple single-body structure three-dimensional models of mid-span adjustable tilt flexible photovoltaic brackets are established, and multiple single-body structure three-dimensional models are evenly arranged to establish a multi-body evenly distributed array three-dimensional model. It should be noted that the inclination angle of the photovoltaic module in each single-body structure three-dimensional model in the multi-body evenly distributed array three-dimensional model is preset to the first initial angle. Then, based on the multi-body evenly distributed array three-dimensional model, a second wind field model corresponding to the multi-body evenly distributed array three-dimensional model is established, and the angle between the second wind field model and the windward surface of the multi-body evenly distributed array three-dimensional model is preset to the second initial angle. Finally, the second wind field model is used to perform resonance monitoring on the mid-span adjustable tilt flexible photovoltaic bracket.

[0083] In the present application, the design parameters of a mid-span adjustable tilt flexible photovoltaic bracket are obtained; a single-body structure three-dimensional model and a multi-body uniformly distributed array three-dimensional model of the mid-span adjustable tilt flexible photovoltaic bracket are respectively established according to the design parameters; a first wind field model corresponding to the single-body structure three-dimensional model and a second wind field model corresponding to the multi-body uniformly distributed array three-dimensional model are respectively established according to the single-body structure three-dimensional model and the multi-body uniformly distributed array three-dimensional model; based on the first wind field model, the mid-span adjustable tilt flexible photovoltaic bracket is strength checked; based on the second wind field model, the mid-span adjustable tilt flexible photovoltaic bracket is resonance monitored. In this embodiment, a first wind field model is established to conduct numerical wind tunnel tests on a single-body structure three-dimensional model to perform strength verification on a mid-span flexible photovoltaic bracket with adjustable tilt. Also, a second wind field model is established to conduct numerical wind tunnel tests on a multi-body uniformly distributed array three-dimensional model to perform resonance monitoring on the mid-span flexible photovoltaic bracket with adjustable tilt. Not only is a single target used as a test object for the numerical wind tunnel test, but the influence of the interaction between multiple targets on the test results is also taken into account, thereby improving the accuracy of the numerical wind tunnel test results.

[0084] In a preferred embodiment of the present application, the step S4 performs strength verification on the mid-span adjustable tilt flexible photovoltaic bracket based on the first wind field model, specifically comprising:

[0085] S4.1. In the first wind field model, select a first preset turbulence model;

[0086] S4.2. Setting a first boundary condition of the first wind field model, the first boundary condition comprising: a first initial pressure and a first initial velocity;

[0087] S4.3. Based on the first preset turbulence model and the first boundary condition, a numerical wind tunnel calculation is performed by finite element analysis software to determine wind pressure parameters distributed on the photovoltaic panels of the three-dimensional model of the single structure;

[0088] S4.4 determining the shape coefficient of the three-dimensional model of the single structure and the gust coefficient of the wind load in the first wind field model according to the wind pressure parameter;

[0089] S4.5. Based on the shape coefficient and the gust coefficient, the strength of the photovoltaic bracket of the single-body structure three-dimensional model is checked by using the wind load statics equation.

[0090] Specifically, in this embodiment, by selecting a first preset turbulence model in the first wind field model; setting the first boundary condition of the first wind field model, the first boundary condition includes: a first initial pressure and a first initial velocity; based on the first preset turbulence model and the first boundary condition, numerical wind tunnel calculation is performed through finite element analysis software to determine the wind pressure parameters distributed on the photovoltaic panels of the three-dimensional model of the single structure; according to the wind pressure parameters, the body coefficient of the three-dimensional model of the single structure and the gust coefficient of the wind load in the first wind field model are determined; according to the body coefficient and the gust coefficient, the photovoltaic bracket of the three-dimensional model of the single structure is strength-checked through the static equation of the wind load. This embodiment simulates a real wind field in reality by selecting a pre-set first turbulence model in the first wind field model, wherein, after selecting the first turbulence model, the first boundary condition of the first wind field model, i.e., the initial condition applied to the first turbulence model in the first wind field model, is further determined: the first initial pressure and the first initial velocity. Furthermore, based on the first turbulence model and the first boundary condition applied to the first turbulence model, numerical wind tunnel calculations are performed using finite element analysis software to determine the wind pressure parameters distributed on the photovoltaic panels of the monomer structure three-dimensional model when the first turbulence model in the first wind field model applies a wind load to the monomer structure three-dimensional model at the first initial pressure and the first initial velocity. Based on the wind pressure parameters, the shape coefficient of the monomer structure three-dimensional model and the gust coefficient of the wind load in the first wind field model are determined, and the strength of the photovoltaic bracket of the monomer structure three-dimensional model is checked based on the shape coefficient and the gust coefficient using the existing wind load statics equation.

[0091] In a preferred embodiment of the present application, the strength verification of the photovoltaic bracket of the single-structure three-dimensional model through the wind load statics equation includes: obtaining the structural strength of the photovoltaic bracket of the single-structure three-dimensional model; calculating the strength of the wind load acting on the photovoltaic bracket in the first wind field model through the wind load statics equation; and performing strength verification of the photovoltaic bracket of the single-structure three-dimensional model based on the structural strength of the photovoltaic bracket and the strength of the wind load acting on the photovoltaic bracket.

[0092] Specifically, in this embodiment of the present application, the structural strength of the photovoltaic bracket of the monomer structure three-dimensional model is obtained; the strength of the wind load acting on the photovoltaic bracket in the first wind field model is calculated by the static equation of the wind load; based on the structural strength of the photovoltaic bracket and the strength of the wind load acting on the photovoltaic bracket, the strength of the photovoltaic bracket of the monomer structure three-dimensional model is checked. In this embodiment, it is first necessary to determine the structural strength of the photovoltaic bracket according to the design parameters of the photovoltaic bracket in the monomer structure three-dimensional model, and the maximum load that the photovoltaic bracket can withstand can be determined by the structural strength. Through the static equation of the wind load, based on the shape coefficient and the gust coefficient, the strength of the wind load acting on the photovoltaic bracket in the first wind field model is calculated, that is, the thrust of the wind load on the photovoltaic bracket in the first wind field model is obtained. Finally, the structural strength of the photovoltaic bracket is compared with the strength of the wind load, that is, the maximum load that the photovoltaic bracket can withstand and the thrust of the wind load on the photovoltaic bracket are compared, so as to check the strength of the photovoltaic bracket of the monomer structure three-dimensional model.

[0093] In a preferred embodiment of the present application, step S4 further includes:

[0094] S4.6. When the structural strength of the photovoltaic bracket in the three-dimensional model of the single structure is lower than the strength of the wind load acting on the photovoltaic bracket, the structural strength of the photovoltaic bracket in the three-dimensional model of the single structure is strengthened.

[0095] Specifically, by checking the strength of the photovoltaic bracket of the single-body structure three-dimensional model, it can be determined whether the photovoltaic bracket can withstand the wind load in the first wind field model. If the structural strength of the photovoltaic bracket of the single-body structure three-dimensional model is lower than the strength of the wind load acting on the photovoltaic bracket, the structural strength of the photovoltaic bracket needs to be adjusted. In practical applications, the structural strength of the photovoltaic bracket can be improved by selecting stronger materials or increasing the thickness of the bracket. This application does not make specific limitations here.

[0096] In a preferred embodiment of the present application, step S7 performs resonance monitoring on the mid-span adjustable tilt flexible photovoltaic bracket based on the second wind field model, specifically comprising the following steps:

[0097] S7.1. In the second wind field model, select a second preset turbulence model;

[0098] S7.2. Setting a second boundary condition of the second wind field model, the second boundary condition comprising: a second initial pressure and a second initial velocity;

[0099] S7.3. Based on the second preset turbulence model and the second boundary condition, a numerical wind tunnel calculation is performed by finite element analysis software to determine the transition flow characteristics between any two adjacent three-dimensional models of the single structure in the multi-body uniformly distributed array three-dimensional model;

[0100] S7.4. Determine whether resonance occurs between any two adjacent three-dimensional models of the monomer structure according to the transition flow characteristics.

[0101] Specifically, in this embodiment, in the second wind field model, a second preset turbulence model is selected; a second boundary condition of the second wind field model is set, and the second boundary condition includes: a second initial pressure and a second initial velocity; based on the second preset turbulence model and the second boundary condition, a numerical wind tunnel calculation is performed by finite element analysis software to determine the transition flow characteristics between any two adjacent monomer structure three-dimensional models in the multi-body uniformly distributed array three-dimensional model; according to the transition flow characteristics, whether resonance occurs between any two adjacent monomer structure three-dimensional models. This embodiment simulates the real wind field in reality by selecting a pre-set second turbulence model in the second wind field model, wherein after selecting the second turbulence model, the second boundary condition of the second wind field model, i.e., the starting condition applied to the second turbulence model in the second wind field model, is further determined: the second initial pressure and the second initial velocity. Further, based on the second turbulence model and the second boundary condition applied to the second turbulence model, a numerical wind tunnel calculation is performed by finite element analysis software to determine the transition flow characteristics between any two adjacent monomer structure three-dimensional models in the multi-body uniformly distributed array three-dimensional model, and based on the information of the transition flow characteristics, we can judge whether resonance occurs between two adjacent brackets. It is important to note that resonance is when the bracket is excited by the wind and its vibration frequency matches the frequency of the wind, which may cause damage or destruction to the bracket. Through this step, we can identify potential resonance problems and take measures to prevent resonance from occurring.

[0102] In a preferred embodiment of the present application, determining whether resonance occurs between any two adjacent three-dimensional models of the monomer structure based on the transition flow characteristics includes: determining the oscillation frequency of the transition flow based on the transition flow characteristics; performing modal analysis on any two adjacent three-dimensional models of the monomer structure in the multi-body uniformly distributed array three-dimensional model using finite element analysis software to determine the vibration frequency corresponding to the free vibration mode of any two adjacent three-dimensional models of the monomer structure; and determining that resonance occurs between any two adjacent three-dimensional models of the monomer structure when the oscillation frequency of the transition flow is the same as the vibration frequency corresponding to the free vibration mode.

[0103] Specifically, in this embodiment, according to the characteristics of the transition flow, the swing frequency of the transition flow is determined; the modal analysis of any two adjacent monomer structure three-dimensional models in the multi-body uniformly distributed array three-dimensional model is performed using finite element analysis software to determine the vibration frequency corresponding to the free vibration mode of any two adjacent monomer structure three-dimensional models; when the swing frequency of the transition flow is the same as the vibration frequency corresponding to the free vibration mode, it is determined that resonance will occur between any two adjacent monomer structure three-dimensional models. In this embodiment, a pre-set second turbulence model is selected in the second wind field model to simulate the real wind field in reality, and a wind load is applied to the multi-body uniformly distributed array three-dimensional model by determining the second boundary condition of the second wind field model, that is, the initial condition of the second turbulence model applied to the second wind field model: the second initial pressure and the second initial velocity, and the simulation results are observed to determine the characteristics of the transition flow, thereby determining the swing frequency of the transition flow according to the characteristics of the transition flow, wherein the swing frequency of the transition flow refers to the frequency of the wind swinging between the brackets, that is, the oscillation frequency of the wind flow in space. Furthermore, finite element analysis software is used to perform modal analysis on any two adjacent monomer structure three-dimensional models, so that the vibration frequency between the photovoltaic brackets of any two adjacent monomer structure three-dimensional models in the free vibration mode can be determined, wherein the vibration frequency under the free vibration mode characterizes the free vibration characteristics of the photovoltaic bracket when not subjected to external forces. Then, the swing frequency of the transition flow is compared with the vibration frequency corresponding to the free vibration mode of the photovoltaic bracket of any two adjacent monomer structure three-dimensional models. If the swing frequency of the transition flow is the same as the vibration frequency corresponding to the free vibration mode, it can be determined that resonance will occur between the two adjacent monomer structure three-dimensional models, that is, resonance will occur between the photovoltaic brackets of the two adjacent monomer structure three-dimensional models.

[0104] In an exemplary embodiment, the above-mentioned multi-body uniformly distributed array three-dimensional model can also be placed in the finite element analysis software, and the swing frequency and amplitude of the transition flow are used as the initial simulation boundary conditions. The finite element analysis software is run to observe whether the amplitude of the photovoltaic bracket changes suddenly. During this period, the swing frequency of the initial simulation boundary conditions can be continuously changed, and the change of the amplitude of the photovoltaic bracket can be continuously observed. If the amplitude of the photovoltaic bracket suddenly increases when the swing frequency is adjusted near a certain position, it is judged that the frequency is the resonant frequency of the photovoltaic bracket. Specifically, Figure 4 The schematic diagram of the frequency and amplitude change relationship curve of the mid-span adjustable tilt flexible photovoltaic bracket is shown. When the resonant frequency is adjusted to 150HZ-250HZ bracket, the amplitude suddenly increases, then it can be determined that the resonant frequency of the photovoltaic bracket is 150HZ-250HZ.

[0105] In a preferred embodiment of the present application, step S7 performs resonance monitoring on the mid-span adjustable tilt flexible photovoltaic support based on the second wind field model, and further includes:

[0106] S7.5. When it is determined that resonance will occur between any two adjacent three-dimensional models of the monomer structure, the structural parameters of the photovoltaic brackets of the two adjacent three-dimensional models of the monomer structure are corrected.

[0107] In this embodiment, when it is determined that resonance will occur between two adjacent single-body structure three-dimensional models of photovoltaic brackets, the structural parameters of the two adjacent brackets need to be corrected. This can avoid the resonance phenomenon, thereby avoiding damage to the bracket or degradation of performance due to enhanced vibration of the bracket. In practical applications, by adjusting the structural parameters of the two brackets, such as material, shape or size, their vibration frequency can be changed to ensure that they no longer match the swing frequency of the transition flow in the wind field, thereby avoiding resonance and increasing the stability and reliability of the photovoltaic bracket.

[0108] In a preferred embodiment of the present application, the first wind field model is established according to the monomer structure three-dimensional model in step S3, including: taking the monomer structure three-dimensional model as a reference, establishing the entrance of the first wind field model at a first preset distance from the windward side of the monomer structure three-dimensional model, establishing the exit of the first wind field model at a second preset distance from the leeward side of the monomer structure three-dimensional model, and establishing the boundaries of the first wind field model at third preset distances from both sides and the top of the monomer structure three-dimensional model.

[0109] Specifically, if Figure 5 The schematic diagram of the structure of the edge space of the first wind field model and the monomer structure three-dimensional model is shown. In this embodiment, firstly, the monomer structure three-dimensional model is used as a reference, starting from the windward surface of the monomer structure three-dimensional model, the entrance of the first wind field model is established at a first preset distance from the windward surface, and this entrance is the starting point of the first wind field model; on the leeward surface of the monomer structure three-dimensional model, the exit of the first wind field model is established at a second preset distance from the leeward surface, and this exit is the end point of the first wind field model; on both sides and above the monomer structure three-dimensional model, the boundaries of the first wind field model are respectively established, and the distances of these boundaries from the two sides and the sky of the monomer structure three-dimensional model are the third preset distances, and these boundaries define the boundary conditions of the first wind field model to ensure that the simulated wind field environment is as close as possible to the real wind field conditions.

[0110] In a preferred embodiment of the present application, the second wind field model is established according to the multi-body evenly distributed array three-dimensional model in step S6, including: taking the multi-body evenly distributed array three-dimensional model as a reference, establishing the entrance of the second wind field model at a first preset distance from the windward side of the multi-body evenly distributed array three-dimensional model, establishing the exit of the second wind field model at a second preset distance from the leeward side of the multi-body evenly distributed array three-dimensional model, and establishing the boundary of the second wind field model at a third preset distance from both sides and the top of the multi-body evenly distributed array three-dimensional model.

[0111] Specifically, in this embodiment, firstly, taking the multi-body evenly distributed array three-dimensional model as a reference, starting from the windward side of the multi-body evenly distributed array three-dimensional model, an entrance of the second wind field model is established at a first preset distance from the windward side, and this entrance is the starting point of the second wind field model; on the leeward side of the multi-body evenly distributed array three-dimensional model, an exit of the second wind field model is established at a position at a second preset distance from the leeward side, and this exit is the end point of the second wind field model; on both sides and above the multi-body evenly distributed array three-dimensional model, boundaries of the second wind field model are respectively established, and the distances between these boundaries and both sides and above the multi-body evenly distributed array are a third preset distance, and these boundaries define the boundary conditions of the second wind field model to ensure that the simulated wind field environment is as close to the actual wind field conditions as possible.

[0112] In a preferred embodiment of the present application, the first initial angle is 5 degrees, the first preset interval angle is 5 degrees, and adjusting the first initial angle according to the first preset interval angle includes: taking the first initial angle of 5 degrees as a reference, and adjusting the first initial angle to 10 degrees, 15 degrees, 20 degrees, 25 degrees, and 30 degrees respectively according to the first preset interval angle of 5 degrees.

[0113] Specifically, refer to Figure 6 The schematic diagram of the component inclination of a mid-span adjustable inclination flexible photovoltaic bracket is shown, with a component inclination of 5 degrees as the initial angle, and then the initial angle is adjusted at intervals of 5 degrees, specifically starting from 5 degrees, and adjusting the component inclination to 10 degrees, 15 degrees, 20 degrees, 25 degrees, and 30 degrees in sequence, so as to conduct tests at a series of angles. The present application analyzes the resonance between photovoltaic brackets through numerical wind tunnel tests at component inclinations of different angles, and adjusts parameters for brackets with resonance at different angles, thereby helping to improve the stability of the photovoltaic bracket. In an embodiment of the present application, by adjusting the inclination of the photovoltaic component in the three-dimensional model of the monomer structure, and based on the first wind field model, the strength of the mid-span adjustable inclination flexible photovoltaic bracket is re-checked; and / or, the inclination of the photovoltaic component in the three-dimensional model of the multi-body uniformly distributed array is adjusted, and based on the second wind field model, the resonance monitoring of the mid-span adjustable inclination flexible photovoltaic bracket is re-performed.

[0114] In a preferred embodiment of the present application, the second initial angle is 0 degrees, and the second preset interval angle is 15 degrees, and adjusting the second initial angle according to the second preset interval angle includes: taking the second initial angle of 0 degrees as a reference, and adjusting the second initial angle to 15 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees, 90 degrees, 105 degrees, 120 degrees, 135 degrees, 150 degrees, 165 degrees, and 180 degrees respectively according to the second preset interval angle of 15 degrees.

[0115] Specifically, refer to Figure 7-19 In this embodiment, in the initial case, the second initial angle, i.e., the angle between the inlet of the second wind field model and the windward surface of the multi-body uniformly distributed array three-dimensional model, is set to 0 degrees, and then the second initial angle is adjusted at intervals of 15 degrees each time to perform multi-angle simulation tests. The specific adjustment sequence is as follows: 0 degrees, 15 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees, 90 degrees, 105 degrees, 120 degrees, 135 degrees, 150 degrees, 165 degrees, 180 degrees. The present application conducts numerical wind tunnel tests at different angles between the inlet of the second wind field model and the windward surface of the multi-body uniformly distributed array three-dimensional model to analyze the resonance between photovoltaic brackets, and adjusts parameters for brackets with resonance at different angles, thereby helping to improve the stability of photovoltaic brackets. In an embodiment of the present application, the entrance angle between the single structure three-dimensional model and the first wind field model is adjusted, and based on the first wind field model, the strength of the mid-span adjustable tilt flexible photovoltaic bracket is re-checked; and / or, the entrance angle between the multi-body uniformly distributed array three-dimensional model and the second wind field model is adjusted, and based on the second wind field model, the resonance monitoring of the mid-span adjustable tilt flexible photovoltaic bracket is re-performed.

[0116] The embodiment of the present application provides a numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic bracket, the method comprising: S1, obtaining design parameters of the mid-span adjustable tilt flexible photovoltaic bracket;

[0117] S2. According to the design parameters, a three-dimensional model of the monomer structure of the mid-span adjustable tilt flexible photovoltaic bracket is established with the inclination angle of the photovoltaic module as the first initial angle; S3. According to the three-dimensional model of the monomer structure, a first wind field model is established, and the angle between the inlet of the first wind field model and the windward surface of the three-dimensional model of the monomer structure is the second initial angle; S4. Based on the first wind field model, the strength of the mid-span adjustable tilt flexible photovoltaic bracket is checked; S5. Multiple three-dimensional models of the monomer structure are evenly arranged to establish a three-dimensional model of a multi-body evenly distributed array; S6. According to the three-dimensional model of the multi-body evenly distributed array, a second wind field model is established, and the angle between the inlet of the second wind field model and the windward surface of the three-dimensional model of the evenly distributed array is the second initial angle; S7. Based on the second wind field model, resonance monitoring is performed on the mid-span adjustable tilt flexible photovoltaic bracket; S8. The first initial angle is adjusted according to the first preset interval angle, and steps S1-S7 are repeated; S9. The second initial angle is adjusted according to the second preset interval angle, and steps S1-S8 are repeated. The present application establishes a first wind field model to conduct numerical wind tunnel tests on a single-body structure three-dimensional model to perform strength verification on a mid-span flexible photovoltaic bracket with adjustable tilt, and establishes a second wind field model to conduct numerical wind tunnel tests on a multi-body uniformly distributed array three-dimensional model to perform resonance monitoring on the mid-span flexible photovoltaic bracket with adjustable tilt. Not only does the numerical wind tunnel test take a single target as the test object, but also takes into account the impact of the interaction between multiple targets on the test results, thereby improving the accuracy of the numerical wind tunnel test results.

[0118] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0119] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present application.

[0120] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0121] The above is a detailed introduction to the numerical wind tunnel analysis method of a mid-span adjustable inclination flexible photovoltaic bracket provided by the present application. This article uses specific examples to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea; at the same time, for general technical personnel in this field, based on the ideas of the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic support, characterized in that: The method comprises: S1. Obtain design parameters of mid-span adjustable tilt flexible photovoltaic support; S2. According to the design parameters, a three-dimensional model of the monomer structure of the mid-span adjustable tilt flexible photovoltaic support is established with the tilt angle of the photovoltaic module as the first initial angle; S3. Establishing a first wind field model according to the three-dimensional model of the monomer structure, wherein the angle between the inlet of the first wind field model and the windward surface of the three-dimensional model of the monomer structure is a second initial angle; S4. Based on the first wind field model, performing strength verification on the mid-span adjustable tilt flexible photovoltaic support; S5, evenly arranging the plurality of said monomer structure three-dimensional models to establish a multi-body evenly distributed array three-dimensional model; S6. Establishing a second wind field model according to the multi-body uniformly distributed array three-dimensional model, wherein the angle between the inlet of the second wind field model and the windward surface of the uniformly distributed array three-dimensional model is the second initial angle; S7. Based on the second wind field model, performing resonance monitoring on the mid-span adjustable tilt flexible photovoltaic support; S8, adjusting the first initial angle according to a first preset interval angle, and repeating steps S1-S7; S9. Adjust the second initial angle according to a second preset interval angle, and repeat steps S1-S8.

2. The numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic bracket according to claim 1 is characterized in that: The step S4 comprises: S4.

1. In the first wind field model, select a first preset turbulence model; S4.

2. Setting a first boundary condition of the first wind field model, the first boundary condition comprising: a first initial pressure and a first initial velocity; S4.

3. Based on the first preset turbulence model and the first boundary condition, a numerical wind tunnel calculation is performed by finite element analysis software to determine wind pressure parameters distributed on the photovoltaic panels of the three-dimensional model of the single structure; S4.4 determining the shape coefficient of the three-dimensional model of the single structure and the gust coefficient of the wind load in the first wind field model according to the wind pressure parameter; S4.

5. Based on the shape coefficient and the gust coefficient, the strength of the photovoltaic bracket of the single-body structure three-dimensional model is checked by using the wind load statics equation.

3. The numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic support according to claim 2 is characterized in that: The strength check of the photovoltaic support of the three-dimensional model of the single structure is performed by using the static equation of wind load, including: Obtaining the structural strength of the photovoltaic support of the single structure three-dimensional model; By using the wind load statics equation, the intensity of the wind load acting on the photovoltaic support in the first wind field model is calculated; Based on the structural strength of the photovoltaic bracket and the strength of the wind load acting on the photovoltaic bracket, the photovoltaic bracket of the single-body three-dimensional model is strength-checked.

4. The numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic support according to claim 3 is characterized in that: The step S4 further comprises: S4.

6. When the structural strength of the photovoltaic bracket in the three-dimensional model of the single structure is lower than the strength of the wind load acting on the photovoltaic bracket, the structural strength of the photovoltaic bracket in the three-dimensional model of the single structure is strengthened.

5. The numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic support according to claim 1 is characterized in that: The step S7 comprises: S7.

1. In the second wind field model, select a second preset turbulence model; S7.

2. Setting a second boundary condition of the second wind field model, the second boundary condition comprising: a second initial pressure and a second initial velocity; S7.

3. Based on the second preset turbulence model and the second boundary condition, a numerical wind tunnel calculation is performed by finite element analysis software to determine the transition flow characteristics between any two adjacent three-dimensional models of the single structure in the multi-body uniformly distributed array three-dimensional model; S7.

4. Determine whether resonance occurs between any two adjacent three-dimensional models of the monomer structure according to the transition flow characteristics.

6. The numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic support according to claim 5 is characterized in that: The step of determining whether resonance occurs between any two adjacent three-dimensional models of the monomer structure according to the transition flow characteristics comprises: determining a swing frequency of the transition flow according to the transition flow characteristics; Performing modal analysis on any two adjacent three-dimensional models of the monomer structure in the multi-body uniformly distributed array three-dimensional model using finite element analysis software to determine the vibration frequency corresponding to the free vibration mode of any two adjacent three-dimensional models of the monomer structure; When the oscillation frequency of the transitional flow is the same as the vibration frequency corresponding to the free vibration mode, it is determined that resonance occurs between any two adjacent three-dimensional models of the monomer structure.

7. The numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic support according to claim 6 is characterized in that: The step S7 further comprises: S7.

5. When it is determined that resonance will occur between any two adjacent three-dimensional models of the monomer structure, the structural parameters of the photovoltaic brackets of the two adjacent three-dimensional models of the monomer structure are corrected.

8. The numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic support according to claim 1 is characterized in that: The step S3 of establishing a first wind field model according to the three-dimensional model of the monomer structure includes: Taking the monomer structure three-dimensional model as a reference, the entrance of the first wind field model is established at a first preset distance from the windward side of the monomer structure three-dimensional model, the exit of the first wind field model is established at a second preset distance from the leeward side of the monomer structure three-dimensional model, and the boundaries of the first wind field model are established at third preset distances from both sides and the top of the monomer structure three-dimensional model.

9. The numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic support according to claim 1 is characterized in that: The step S6 of establishing a second wind field model according to the multi-body uniformly distributed array three-dimensional model includes: Taking the multi-body evenly distributed array three-dimensional model as a reference, the entrance of the second wind field model is established at a first preset distance from the windward side of the multi-body evenly distributed array three-dimensional model, the exit of the second wind field model is established at a second preset distance from the leeward side of the multi-body evenly distributed array three-dimensional model, and the boundaries of the second wind field model are established at third preset distances from both sides and above the multi-body evenly distributed array three-dimensional model.

10. The numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic support according to claim 1, characterized in that: The first initial angle is 5 degrees, the first preset interval angle is 5 degrees, and the adjusting the first initial angle according to the first preset interval angle includes: Taking the first initial angle of 5 degrees as a reference, according to the first preset interval angle of 5 degrees, the first initial angle is adjusted to 10 degrees, 15 degrees, 20 degrees, 25 degrees, and 30 degrees respectively.

11. The numerical wind tunnel analysis method for a mid-span adjustable tilt flexible photovoltaic support according to claim 1, characterized in that: The second initial angle is 0 degrees, the second preset interval angle is 15 degrees, and the adjusting the second initial angle according to the second preset interval angle includes: Taking the second initial angle of 0 degrees as a reference, according to the second preset interval angle of 15 degrees, the second initial angle is adjusted to 15 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees, 90 degrees, 105 degrees, 120 degrees, 135 degrees, 150 degrees, 165 degrees, and 180 degrees respectively.

Images